1. Field of the Invention
The present invention relates to bottom end attaching portions of fastener tapes and a slide fastener chain including the same wherein end portions of tapes are reinforced in two manners (i.e., strongly and weakly) in order to mount a box pin, a box, and an insert pin to end portions of the fastener tapes of the slide fastener of a separable type having a bottom end stop, thereby firmly fixing the bottom end stop and can be used for a long time.
2. Description of the Related Art
Conventionally, in this separable type of a slide fastener, there is a separable type of well known slide fastener, wherein attaching portions are formed for mounting the bottom end stop to end portions of fastener tapes by bonding narrow taffeta to the end portions of the fastener tapes to harden the entire tapes, so that the box pin, the box, and the insert pin can be mounted to the attaching portions at side edges of hardened fastener tapes.
As an improved bottom end stop attaching portions for the above separable type of slide fastener, as shown in FIG. 6, there are bottom end stop attaching portions as disclosed in Japanese Utility Model Laid-Open Publication No. 44-25842, wherein synthetic resin liquid is coated on end portions of tapes, or synthetic resin film is fused with the end portions of tapes, or taffeta is bonded to the end portions of tapes so as to harden one side edges or both side edges of the tapes to a great extent excluding sewing portions which are hardened to some extent. The box pin, the box, and the insert pin are mounted to this edge portions hardened to a great extent. By partly changing hardness of the fastener tapes, the bottom end stop can be firmly attached and the slide fastener can be easily attached and sewn.
As shown in FIG. 7, there are bottom end stop attaching portions of a slide fastener as disclosed in Japanese Utility Model Publication No. 56-25524, wherein synthetic resin film or auxiliary tape such as taffeta is bonded in two manners (i.e., strongly and weakly) to entire end portions of the fastener tapes to form at the bonded portions, stiff and flat strongly bonded portions and weakly bonded portions which are dotted and highly projecting as compared with the strongly bonded portions, in order to apply proper stiffness and strength to entire bottom end stop attaching portions, and to prevent bending, cracking, and the like of the bottom end stop attaching portions when using the slide fastener, and to prevent sewing yarn being cut by hardened reinforcing portions.
The bottom end stop attaching portions of the separable type of slide fasteners described above and shown in FIGS. 6 and 7, the strongly bonded portions and the weakly bonded portions formed in two manners (i.e., strongly and weakly) are formed at the bonded portions with reinforcing portions such as synthetic resin film and taffeta are bonded to faces of the tapes. However, in both of the above described the bottom end attaching portions, portions to which the box pin, the box, and the insert pin are attached are weakened by excessive pressurizing and heating, and by a twisting force caused when using the slider fastener, crack is made at attachment part of the box pin and the insert pin mounted to the reinforced portions to which the bottom end stop is attached such that separating and inserting operations can not be carried out smoothly.